NO_UNIQUE_KEY schema lint error

table "orders" has no non-null unique key: all tables must have at least one unique, not-null key without using text / blob columns or partial indexes.

CREATE TABLE orders (
  id bigint unsigned NOT NULL,
  customer_id bigint unsigned NOT NULL,
  created_at datetime NOT NULL,
  PRIMARY KEY (id)
);

ALTER TABLE orders MODIFY id bigint unsigned NOT NULL;
ALTER TABLE orders ADD UNIQUE KEY orders_id_idx (id);